A collector that has enough
hardness and flexibility and a
battery electrode substrate that uses this collector are provided. Also provided is a low-cost
battery electrode substrate that exhibits excellent high-rate charge /
discharge characteristics and low electrical resistance and that is able to avoid the decline in cycle characteristics caused by repetitive charging / discharging. The invention is a
battery electrode substrate having a structure in which a
nickel film is coated on the surface of
plastic fiber of a woven or unwoven fabric, wherein a metallic porous body in which the average
coverage ratio by the
nickel film is not less than 85% is used. The invention is also a collector comprising a metallic porous body having a structure in which a surface of
plastic fiber of a woven or unwoven fabric is coated with a
nickel film so as to be an average
coverage ratio of not less than 85%, wherein the metallic porous body comprises at least two
layers of a lower density region and a higher density region in the thickness direction between which there is a difference in density of included nickel, and a thickness of the lower density region is not less than 1.5-times a thickness of the higher density region. The invention is also a battery
electrode substrate that has a structure in which a surface of a
plastic fiber in a unwoven fabric is coated with a nickel film, wherein the battery
electrode substrate uses a metallic porous body in which a transverse-to-longitudinal ratio of the electrical resistance is not less than two times. The plastic
fiber is preferably a
fiber that has a core / sheath composite
fiber structure in which the core is
polypropylene and the sheath is
polyethylene.